Product Properties and Processing - Kraiburg...

ReferencesFigures 2, 5, 6 and 7 (s. THERMOLAST® in Injection Moulding/Moulds) are based on„Spritzgieß-Werkzeuge“(5. issue, 1999), edited by Menges,Michaeli and Mohren, published byCarl Hanser Verlag (S. 161, 165 and 166)

The information in this publication is based on our current knowledge and experience. In view of the many factors that may affect processing and application, this information does not relie-ve processors of the responsibility to carry out their own tests and experiments; nor does it imply and legally binding assurance of certain properties or of suitability for a specific purpo-se. It is the responsibility of those to whom we supply our products to ensure that any proprie-tary rights and existing laws and legislation are observed.

KTPE-Form 17GB-5/August 2010

THERMOLAST®

Product Propertiesand Processing

46 3

1. THERMOLAST® K Melt Compounds

THERMOLAST® K Melt compounds feature extremely low melt viscosity.

The main advantage provided by these compounds is their processability

without need for shearing, i.e. their extremely low melt viscosity at the

specified processing (melt) temperature permits casting, spraying or other

coating procedures on surfaces.

THERMOLAST® K Melt compounds can be held at their specified processing

temperature for up to a day without substantially reducing viscosity.

2. Supply Mode

THERMOLAST® K Melt compounds are supplied as pellets. Please note

that these compounds are TPE and they should not be mistaken for hotmelt

adhesives.

3. Possible Application Sectors

The pressure-free processability of THERMOLAST® K Melt compounds

makes them ideal for coating of textiles, cardboard etc. – for instance in

removable protective coatings.

Further information regarding application sectors, advantages and processing

recommendations for THERMOLAST® K Melt compounds can be obtained

from us or at www.kraiburg-tpe.com.

This brochure provides a broad overview of THERMOLAST® including properties and processing techniques.Recommendations are offered for equipment and tooling which will help ensure successful manufacturingof products made from THERMOLAST®.

THERMOLAST® is a trade name for three high-performance TPE product groups: THERMOLAST® K, THERMOLAST® V and THERMOLAST® A. Most THERMOLAST® compounds are based on hydrogenatedstyrene block copolymers (HSBC).

THERMOLAST® KTHERMOLAST® K compounds are the largest product family in the KRAIBURG TPE portfolio. Availablewith a wide range of modifications, they provide outstanding properties in a wide variety ofapplication fields. Many years of experience and extensive development work on product and application-specific projects have brought about a unique range of THERMOLAST® K compound series.These compounds fulfil key requirements in a broad spectrum of industries and application sectorsand provide cost-effective and reliable solutions for perfect end products.The most commonly used conversion processes for THERMOLAST® K compounds are injectionmoulding and extrusion. A special compound series is also available for hot melt processing.

THERMOLAST® MThe product line THERMOLAST® M provides a safe and high-quality basis for the products of the customers from the medical and pharmaceutical industry. The purpose of the project THERMOLAST® M was the development of a product which meets the high standards for safety, quality and reliability and which allows a processing up to the liability risk of indirect blood contact. The contents of the THERMOLAST® M Service Packa-ge are exceptional on the market.

THERMOLAST® VTHERMOLAST® V compounds provide superb physical properties in high temperature applications.They also exhibit excellent hysteresis behaviour, outstanding compressive stress relaxation andextremely low long-term compression set at high temperatures. THERMOLAST® V is preferred foruse in automotive (under-the-hood) applications or for gaskets of any kind exposed to high temperatures.THERMOLAST® V compounds are normally processed by injection moulding or extrusion.

THERMOLAST® AOne of the THERMOLAST® A compound series provides enhanced oil resistance even at very lowhardness ratings. The other series offers excellent UV resistance and outstanding adhesion to PC andPC/ABS. Both THERMOLAST® A compound series offer exceptional scratch resistance and superiorwet grip properties. With this combination of properties, THERMOLAST® A is perfect for use in automotiveapplications, manual tools, power tools, etc. THERMOLAST® A is well suited for processingby injection moulding.

A quick overview of our compound series and their most important properties is provided onwww.kraiburg-tpe.com.

Along with our standard compound series, we also offer tailor-made THERMOLAST® compoundsengineered specifically to your individual needs.

Other Processing MethodsTHERMOLAST K Melt Compounds Introduction

44 5

Problem Possible Causes Possible Solutions

Rough extrudate Melt too cold 1. Increase extruder temperature.2. Increase die temperature.

Inhomogeneous melt /undispersed particles

1. Use screw with higher compression ratio or screw with mixing zone.

Poor die design 1. Reduce land length.2. Check dimensions.

Uneven cross section Surging 1. Reduce throughput.2. Use screw with longer feed or metering section.3. Use more restrictive screen pack – e.g. tighter mesh – to increase back pressure.4. Reduce die temperature.

Black specks /Undispersed particles

Contamination 1. Purge with high-MFI PP or HDPE.2. Check that colour concentrate is based on PP or PE - not PVC.

Odour or yellowing Melt too hot 1. Reduce barrel temperature.2. Reduce die temperature.3. Reduce screw speed.4. Use less restrictive screen pack – e.g. larger mesh – to reduce back pressure.5. Use screw with lower compression ratio.

Voids, porosity,craters

Moisture 1. Dry pellets.

High pressure /low throughputin extruder

Melt too cold 1. Increase extruder temperature.2. Increase die temperature.

Obstructed screens 1. Clean or replace screens.

7. Venting ___________________________________________ 8. Recommendations for Tooling Steel 9. Mould Surfaces and Demoulding _____________________ 10. Shrinkage ________________________________________Special Information on Coinjection Moulding _________________ 1. General Information 2. Advantages of Coinjection Moulding 3. Alternative Bonding Methods ________________________ 4. Mechanical Anchoring 5. Adhesion 6. Machinery for Coinjection Moulding __________________ 7. Adhesion Testing of Coinjected Systems _______________ 8. Processing Information for Coinjection Moulding ________ Trouble Shooter Injection Moulding _________________________Summary Injection Moulding ______________________________ 1. Machines and Processing 2. Moulds ___________________________________________ 3. Specials Points in Coinjection Moulding

Machines and Processing _________________________________ 1. Machine Specifications 2. Cleaning of Machines 3. Screws, Screens, Breaker Plate 4. Process Parameters _________________________________ 5. Process Temperatures 6. Die Temperature 7. CalibrationDies ___________________________________________________ 1. Extrusion DiesCoextrusion 1. Combination PossibilitiesTrouble Shooter Extrusion _________________________________Summary Extrusion ______________________________________ 1. Machines and Processing 2. Process Temperatures 3. Dies

Processing Methods for THERMOLAST® K Melt Compounds _____ 1. THERMOLAST® K Melt Compounds 2. Supply Mode 3. Possible Application Sectors

26

272829

30

3132343639

40

41

42

43

4445

46

THERMOLAST® in ExtrusionTrouble Shooter Extrusion

THERMOLAST® inInjection Moulding

THERMOLAST® in Extrusion

Other Processing Methods

42 7

5. Process Temperatures

Typical extrusion process parameters for THERMOLAST® are as follows:

Feed zone: 140 – 160 °C (285 – 320 °F)Compression zone: 150 – 170 °C (300 – 340 °F)Metering zone: 160 – 180 °C (320 – 355 °F)Extruder head: 170 – 180 °C (340 – 355 °F)Die: 180 – 220 °C (355 – 425 °F)

The maximum processing temperature should not exceed 250 °C (480 °F).Higher process temperatures or excessive residence times in the processingunit can result in thermal degradation.Recommended process temperatures for THERMOLAST® compounds canbe found at www.kraiburgtpe.com.

6. Die Temperature

The die temperature should normally be 185 °C (355 °F). More informationcan be found at www.kraiburg-tpe.com. Our applications engineering depart-ment will also be pleased to provide you further information upon request.

7. Calibration

Calibration is normally not required. Support elements may be requiredwhen extruding THERMOLAST® compounds with high hardness or whencoextruding with standard thermoplastics.

Thermoplastics

become free-flowing and shapeable under application of heat and shear force resolidify when cooled purely physical process without chemical transformation or crosslinking thermoforming process is reversible, i.e. can be repeated

Elastomers

initially deformable, can be crosslinked under application of heat crosslinking is a chemical process involving bonding of neighbouring molecular chainsafter crosslinking have elastic properties (high resistance to heat and mechanical stress) crosslinking is irreversible, i.e. material cannot be reshaped by repeated heating

Thermoplastic Elastomers

Based on hydrogenated styrene block copolymers (for example SEBS)

ethylene-butylene network polystyrene domains

under application of heat and shear force, become free-flowing and shapeable molecules are made up of thermoplastic polystyrene end blocks and elastic ethylene-butylene mid-blocks on cooling, physical crosslinks (polystyrene domains) are formed which connect the elastic ethylene-butylene blocks, creating a fixed three-dimensional network as a result, the elastic properties of TPEs are comparable with those of chemically crosslinked elastomers thermoforming process is reversible, allowing problem-free recycling of production scrap without impairing mechanical property levels (see page 14 Point 2. ‘Recycling’)

ethylene-butylene network

polystyrene domains

THERMOLAST® in ExtrusionMachines and Processing Thermoplastics - Elastomers - Thermoplastic Elastomers (TPE)

40 9

2. Moulds

Runner system:

Balanced runner system

Gate: Diameter: 0.4 – 0.6 mm, max. 1.0 mmSprue: Standard, draft angle min. 1.5°, For hardnesses < 70 Shore A, min. 2.5°Runners: Semi-circular, trapezoidal shapes possible best shape: roundGate types: Pin gate, submarine gate, film gateVenting: 0.01 – 0.02 mm (0.0004 – 0.001 in.) vent channelsMould surface: See page 27, Section 9. Mould Surface and DemouldingShrinkage: See page 28, Section 10. Shrinkage

3. SPECIALS POINTS IN COINJECTION MOULDINGSee information provided in “Special Information on CoinjectionMoulding”, starting on page 29.

3. Series Compounds - Significant Features

Excellent adhesion on virtually all common thermoplasticsHighly transparent, available in all coloursHardness grades available from 0 Shore A to 60 Shore DElasticHigh flexibility at low temperaturesSuperb thermal resistanceExcellent electric insulationResistant to hydrolysisResistant to acids and bases

4. THERMOLAST® Compound series

THERMOLAST® compounds fulfil key requirements in a broad range ofindustries and applications fields.

* for coinjected parts, without infringement of Taisei patents US 5149589 and JP 2888305

Application fields Key requirement of different industries Further important properties

Consumer, Care · BfR, FDA, 2002/72/EC · Smooth surface· Adhesion to PP

Medical · USP Class VI· ISO 10993-5 und ISO 10993-10 (no skin and mucous membrane irritation)

· Sterilizable (Gamma, EtO, autoclave)· Extremely flexible· Excellent mechanical properties

Toys · EN 71/3 · Super soft Compounds

Automotive · excellent UV resistance (e.g. Florida test, Kalahari test, VW PV 3930, 3929)

· Improved oil resistance· Emission optimized (automotive interior)· Low density

Electronics / Industries · flame retardant and UL 94 HB, V0 listed· Conforming to RoHS

· Adhesion to conventional technical thermoplastics (in conformance with Taisei patents*)

Construction · excellent UV resistance (e.g. RAL GZ716/1, CSTB/DER/BV-PEM REV01· WRAS and W270 KTW approval

· No interaction with other materials

THERMOLAST® im SpritzgussSummary Injection Moulding

38 11


Poor or no adhesion in coinjection at the beginning / in the middle of the meltflow path

Hold pressure too high(displacement of cooledmaterials at bondinterface)

1. Reduce hold pressure.

Injection rate too low 1. Increase injection rate.

Poor or no adhesionin coinjection at the endof the melt flow path

Processing / mouldtemperatures too low

1. Increase Processing / mould temperatures.

Injection rate too low 1. Increase injection rate.

In transfer processes,(insert moulding) semifinishedpart is too cold

1. Preheat part (caution: heat surface only to approx.80 °C – 100 °C (175 °F – 210 °F). The preheatingprocess should last for only a short period of time;very important when hard component is semicrystalline.

Insufficient venting 1. Reduce clamping force.2. Reduce injection rate.3. Add ejector bore.4. Add venting system.

Poor or no adhesionin coinjection in general

Inappropriate materialcombination

1. Check the material compatibility.

In transfer processes, (insert moulding) semifinished part is not free of grease and dust.

1. Clean semi-finished part (use gloves if necessary).

THERMOLAST® compounds can be designed to specific user requirementsand are therefore available with an extensive range of physicalvalues. Detailed data is provided on our data sheets.

1. Hardness

Compounds are available in hardness ratings ranging from 0 Shore A to60 Shore D. Shore A hardness testing is suitable for compounds withhardness ratings only within the range 10 to 80 Shore A. If the compoundto be tested is softer than 10 Shore A, our IRHD SS test procedure shouldbe used to get accurate results. Further details are provided in our datasheets for super-soft compounds.

2. Tensile Strength and Elongation at Break

The degree of molecular orientation depends on the geometry of thepart moulded and the processing conditions employed. Tensile strengthand elongation at break are greater in the direction perpendicular toorientation. (please also refer to page 25, 6. Types of Gates)

3. Service Temperatures

The permissible service temperature range for THERMOLAST® compoundsis generally from -50 to 120 °C (-58 to 248 °F) and forTHERMOLAST® V from -50 to 140 °C (-58 to 284 °F). Variations arepossible in specific applications depending on the particular types anddurations of stress encountered as well as other factors.

Detailed information on hot air ageing and/or cryogenic behaviour ofTHERMOLAST® can be provided upon request.

THERMOLAST® in Injection MouldingTrouble Shooter Injection Moulding

Product PropertiesPhysical Values

36 13


Incomplete fill Air entrapment due toinsufficient venting

1. Check for obstruction of vents.2. Check vent locations.3. Enlarge vents.4. Change filling behaviour by reducing or increasing injection rate and / or pressure.5. Add vacuum assist to vents.

Runner system 1. Check for obstruction of gate.2. Enlarge gate.3. Enlarge runners.

Melt and / or mouldtoo cold

1. Increase barrel and nozzle temperatures.2. Increase mould temperature.3. Increase injection rate.4. Increase screw speed.

Sink marks(not to be confusedwith air entrapment )

Hold pressure too low 1. Increase holding pressure.

Melt and / or mouldtoo hot

1. Reduce barrel and nozzle temperatures.2. Reduce mould temperature.3. Reduce screw speed.

Charring Melt and / or mouldtoo hot


Heater(s) stuck on 1. Check thermocouples and heater bands.

Odour or yellowing Melt and / or mouldtoo hot

1. Reduce barrel and nozzle temperatures.2. Reduce mould temperature.3. Reduce injection rate.4. Reduce screw speed and back pressure.5. Check temperature of hot runners (if used).

Flashing Injection pressure /rate too high

1. Reduce injection pressure / rate.2. Increase clamp pressure.3. Reduce injection rate.

Melt and / or mouldtoo hot


1. Chemical Resistance

THERMOLAST® compounds exhibit excellent resistance to water and awide variety of aqueous solutions including strong inorganic acids andalkali solutions. However, long-term contact with oils, fuels, aromatics andvarious organic acids can cause a certain amount of degradation. Whetheror not resistance to these substances is sufficient for a given applicationmust be evaluated on a case-by-case basis.As absorption behaviour is highly dependent on the prevailing serviceconditions (e.g. temperature), material tests are normally recommendedunder the actual conditions found in the subsequent application. As mentionedearlier, a number of THERMOLAST® A compounds are availablewith enhanced oil resistance – please contact us for further information.

2. Behaviour in contact with Acrylic Paint

Contact exposure testing shows that THERMOLAST® compounds generallyhave excellent resistance to acrylic paints.A 14-day immersion of a THERMOLAST® test plaque fixed between 2acrylic-painted wooden boards at 50 °C yielded the following test results:No interfacial sticking between the plaque and the boards, no matte spots,no softening, no discolouration and no wetness on the painted boards.Natural-coloured compounds may turn slightly yellow in colour but arenot otherwise attacked or altered by acrylic paint.More details can be provided on request.

THERMOLAST® in Injection MouldingTrouble Shooter Injection Moulding

Product PropertiesEnvironmental Resistance

34 15

THERMOPLASTAdhesion

quality in CoinjectionMoulding with

THERMOLAST®

Transfer Processes ProvidingGood Adhesion Results

ABS > 30 Shore A l

ABS/PC > 30 Shore A

PC > 30 Shore A

PC/PBT > 30 Shore A

PETG > 30 Shore A

PMMA > 50 Shore A

PBT > 30 Shore A l

PP > 0 Shore A

PE > 49 Shore A

PA6 > 25 Shore A

Pa6.6 > 25 Shore A

PA 12 > 25 Shore A

POM (Copolymere from Ticona) > 47 Shore A

PS > 50 Shore A l

HIPS > 50 Shore A l

SAN > 50 Shore A

ASA > 50 Shore A

Materials are available from our standard compound series providingadhesion to the following thermoplastics:

Description of adhesion quality

Very good adhesion, separation in cohesive mode

Good adhesion, separation in adhesive mode, TPE is difficult to pull off

Good results possible in robotic or manual transfer processes (insert moulding) without intermediate storage

Good results possible in transfer processes (insert moulding) with intermediate storage

Preheating of semi-finished part recommended l

Table Comoulding Systems

3. Environmental Compatibility

THERMOLAST® is environmentally friendly. Any scrap which cannot be recycledas described in the previous section can be disposed of in landfills inaccordance with local regulations. When incinerated, THERMOLAST® burnsin a manner similar to polyolefins.Any scrap which cannot be recycled as described in the previous sectioncan be disposed of in landfills in accordance with local regulations.

4. Colouring

Almost all compounds from our standard compound series are transparent ortranslucent and natural-coloured or black in colour. Upon request we can supplyTHERMOLAST® compounds in virtually any colour required. However, inprocesscolouring, e.g. in injection moulding or extrusion, is very simple andnormally far more economical. Due to their natural light colour THERMOLAST®

compounds can be coloured in process, even in light or luminous colours,providing finished products with outstanding visual appearance and offeringsignificant benefits over EPDM/PP.Colouring can be done with universal colour batches. Best results are achievedusing polyolefin batches. Depending on the desired colour to be attained,the batch should be added at a level of around 2 – 5%. Colouring normallydoes not result in significant changes in material properties except for hardnesswhich can increase by up to approx. 2 Shore A depending on theamount of colourant added.Liquid colourants can also be used with THERMOLAST®; however in somecases they cause problems in homogenization and therefore master batches areto be preferred. Compounds which must conform with industry-specific require-ments or specifications (e.g. UL 94, BfR, FDA, excellent UV resistance, etc.)should be coloured with suitable colouring agents to maintain conformance.

Application problems requiring adhesion to other thermoplastics, e.g. PET,PC/PET, PPO/PS, CAP, CAB etc., are often best solved by custom-engi-neered compounds. Please contact us for more information.

8. Processing Information for Coinjection Moulding

The points given below presume use of the normal injection sequence,i.e. injection of the hard component in the first process step, followed byTHERMOLAST® in the second step.The following information and procedures are normally beneficial foroptimum adhesion:

THERMOLAST® in Injection MouldingSpecial Information on Coinjection Moulding

32 17

Hard/soft combinations using THERMOLAST® can be produced using allconfigurations of machinery and possible moulds as mentioned in thetable above. The decision about which technique to choose, and whichgives the most cost-effective solution, depends on many factors. It willbe necessary to take into account, for example, the material that theTHERMOLAST® must bond to, contact surface area and flow length, partgeometry, number of parts to be produced, and machine availability.

7. Adhesion Testing of Coinjected Systems

Important notes concerning the table “Comoulding Systems” on page 34:

Evaluation of adhesion quality is normally highly subjective. As a uniformtest procedure for adhesion evaluation has not yet been established, comparisonof different materials by test data alone is often unreliable.

Evaluation of THERMOLAST® coinjected parts is best done by comparativetesting using our in-house test procedure based on the Renault D41 1916Standard.The experimental set-up shown on the following page shows how a tensiletesting machine is used to measure peel force (units: N/mm) as a functionof upper clamp displacement („peel path“). Displacement prior to peeling isdue to the inherent elasticity of the TPE material. This test method is ahighly useful tool in optimization of adhesion quality in THERMOLAST®

coinjected articles.

Test piece dimensions:Thermoplastic part: 130 x 22 x 2 mm (5.118 x 0.866 x 0.079 in.)TPE part: 130 x 20 x 2 mm (5.118 x 0.787 x 0.079 in.)

8. Adhesive Bonding and Surface Decoration

Adhesive Bonding:Most THERMOLAST® compounds can be joined by adhesives with goodbonding results. The adhesive selected for use must fulfil diverse requirementsin terms of environmental protection, surface appearance and bondingstrength.

The bonding strength of an adhesive depends primarily on the surfacecontact achieved between the components joined. The following rulesshould be followed to ensure optimum adhesion:

Ensure that the surfaces joined are dry and free of foreign material of any type.Apply high pressure to the bond immediately after joining to improve flow of the adhesive and its contact with the surfaces joined.Higher bonding strength can be achieved by increasing contact pressure, contact pressure application time and/or temperature.

The adhesive used must be compatible with the material or materials joined,i.e. it must provide the required strength without attacking (solvating ordissolving) the material or being attacked by the material (e.g. due to plasticizermigration). Your KRAIBURG TPE representative will be pleased torecommend suitable adhesives for specific compounds to be joined.

Surface Decoration:Special THERMOLAST® compounds are available which are suited forprinting, painting, or lacquer coating when appropriate application proceduresare used. We will be happy to provide further information as required.In the event an adhesive or decoration system does not adhere sufficiently,adhesion can normally be improved by suitable pretreatment (e.g. primercoating or corona treatment).


30 19

3. Alternative Bonding Methods

In coinjection moulding, bonding between adjacent components can berealized viamechanical anchoring, oradhesion bonding

Both alternatives are described in detail below, although adhesion bondingis by far more widespread in modern coinjection processes.

4. Mechanical Anchoring

Mechanical anchoring involves no physical bonding between the adjacentmaterials. Connection is realised e.g. by undercuts or interlocking contoursin the semi-finished injection-moulded part.

The drawings shown above illustrate examples of coinjected mouldedparts incorporating interlocking and undercut anchoring. Our applicationsengineering team can provide more information concerning mechanicalanchoring and its feasibility in your specific application.

5. Adhesion

The base polymers used in THERMOLAST® compounds permit outstandingmodification flexibility for optimum adhesion to a wide variety of thermoplastics.

The term adhesion is used to describe physical bonding between adjacentmaterials. Occasionally this type of bonding may be referred to as a “chemicalconnection”. This is in fact incorrect as bonding between thermoplasticsand TPE definitely does not occur via chemical reactions.

4. Barrel and Melt Temperatures

The optimum barrel and melt temperatures for plasticizing differ considerablydepending on the specific compound processed. These temperaturesare of particular importance in 2-component injection (coinjection) mouldingand must be selected in accordance with the compounds processed.Please refer to the Processing Guide provided at www.kraiburg-tpe.com.

As a general rule the barrel temperature should increase progressively by10 to 20 °C (15 to 35 °F) per zone starting from the feed hopper. The nozzletemperature should be equal to or 10 °C (15 °F) below the temperatureof the last heating zone

5. Mould Temperature

The optimum tool temperature is also highly dependent on the specific compoundprocessed, particularly in the case of coinjection moulding.Recommended mould temperatures can be found at www.kraiburg-tpe.com.

As a general rule, we recommend using a tooling temperature of 40 - 60 °Cwhen moulding thin-walled components.

We will be happy to assist you in selecting the correct mould temperaturefor your application, particularly if you are processing a custom-engineeredcompound. We look forward to your enquiry.

6. Injection Pressure and Injection Rate

The injection pressure and injection rate must be selected in accordancewith the melt viscosity and shear sensitivity of the material processed andtherefore will vary for different THERMOLAST® compounds. When processinghigh viscosity compounds, take care to ensure sufficient meltshear rates: The cavity should be filled at high injection pressure and highflow rate (in the range of approx. 100 - 200 g/s).


28 21

10. Shrinkage

Due to the anisotropic behaviour of THERMOLAST® compounds, shrinkagenormally differs in relation to the flow direction in moulding. Ourengineering staff can assist you in design of your moulds and will provideshrinkage data for our test plaques and the process conditions used intheir fabrication.

Please note that shrinkage values from laboratory samples will not correlateon a 1:1 basis with values obtained in practice as shrinkage can beinfluenced by a large number of factors:processing parametersrunner system (hot runner / cold runner)mould temperaturemould designpart geometrymelt temperatureflow directionmaterial processed

Effects on shrinkage when injection moulding conditions are changed:

Changes in injection moulding conditions Effect on shrinkage

T melt - mould

cooling time in mould

mould temperature

injection rate

hold pressure

Effects of higher back pressure:improves distribution e.g. of colour batches and other additivesincreases melt homogeneityplasticizing time is increased for a given screw speedreducing the screw speed also has a positive effect on homogeneitymay cause deformation around the sprue

Effects of lower back pressure:creates insufficient shear energy and inhomogeneous meltas a result, higher-melting components in the compound may not plasticate.

8. Hold Pressure and Hold Time

The mould should be filled initially without applying hold pressure. Lowhold pressure can then be applied to prevent sink marks and to guarantee100% filling. The hold time should be set as short as possible.

Possible effects of high hold pressure:overfilling of cavitiesdifficulties in demouldinglayer formationdeformation around the sprueimproved adhesion at flow linesadditional information concerning coinjection moulding is provided in Section 8. Processing Information for Coinjection Moulding starting on page 34

Possible effects of low hold pressure:sink marks in thick-walled partsincreased shrinkage

THERMOLAST® in Injection MouldingMoulds

26 23

7. Venting

Insufficient venting usually results inincomplete filling of cavitiessurface defectsburn marksinsufficient adhesion within coinjected parts

Apart from avoiding the above problems, optimum venting can also reducecycle times in some cases. Venting can take place at the mould partingline. Usually we recommend that venting is done at a position furthestaway from the gate point or at the position of the joint line. A filling studycan be carried out to determine the correct venting position.Usually vent channel depths of between 0.01 mm (0.0004 in.) and 0.02 mm(0.001 in.) are sufficient to ensure good venting.

8. Recommendations for Tooling Steels

The standard tooling steel grades listed below can normally be used inprocessing equipment for THERMOLAST® compounds:

Material No. Quality HRC Properties Applications Etchable High Gloss Coatable

1.2083 through hardened52 - 54

Cr alloyed steel corro-sion resistant mould surfaces yes yes yes

1.2343 ESU through hardened52 - 54 hot-worked steel mould surfaces yes (yes) yes

1.2344 ESU through hardened52 - 54 hot-worked steel mould surfaces yes (yes) yes

1.2311 through hardened52 - 54 hot-worked steel

mould surfaces(particularly when large in size)

yes yes yes

1.2764 surface hardened58 case-hardened steel mould plates

and inserts yes yes

1.2767 ESU through hardened54 - 56 cold-worked steel mould surfaces yes yes yes

Figure 4: Non-balanced runner systemFlow paths from the sprue to the individual cavities differ in length.Cavities nearer to the sprue are overfilled and those further away are notfilled completely.

3. Gate Points

The excellent rheological characteristics of THERMOLAST® compoundsoften eliminate the need for multiple gate points in large cavities or cavitieswith long flow paths. The following point should be noted with regardto THERMOLAST® rheology: As friction increases, viscosity decreases.The gate point should therefore be located such that the melt contacts awall or core shortly after entering the cavity. Unrestricted flow, i.e. jetting,is to be avoided under all circumstances.

The ratio between the part wall thickness and the sprue diameter is a factor of de-cisive importance. Systems designed in accordance with these points will permit longer flow paths and provide improved part surfaces. Ideally the diameter of the gate point should be between 0.4 and 0.6 mm, with a maximum of 1.0 mm. A small depression (with a lens-like curve) will ensure that the gate point on thepart is very clean.


24 25

4. Sprue

For processing THERMOLAST® compounds we recommend standard sprues with a draft angle of at least 1.5°. When compounds with hardness ratings less than 70 Shore A are processed, the draft angle should be at least 2.5°.

„Z“ type sprue pullers (undercuts) can be used except when processing soft THERMOLAST® compounds. Conical pullers can be used with most compounds.

Figure 5: Figure 6:„Z“ type puller Conical puller

5. Primary and Secondary Runner System

Normally semi-circular or trapezoidal runner channels can be used; however,round runner channels are best as they have a smaller surface areafor a given cross-section. The secondary runner channels to the mouldsshould be large enough to allow the hold pressure to be maintained for asufficient length of time. The diameter of the secondary runners should beslightly smaller than that of the primary runner.

All types of hot runner systems are suitable for use with THERMOLAST®

compounds. Internally heated systems offer some slight advantages.Diameters should be chosen such that the volume of the hot runner issmaller than the finished part. If this is not the case, the hot runner shouldbe empty after a maximum of 2 – 3 shots.

6. Types of Gates

Mechanical properties such as tensile strength and elongation ofTHERMOLAST® injection moulded parts are dependent on the directionof flow in injection. The resultant molecular orientation normally resultsin increased tensile strength and elongation at break perpendicular to theflow path.

The gate should therefore be selected in accordance with the part moulded:In general, submarine or pin gates can be used with THERMOLAST® compounds.As noted above, the gate must be located such that the material contacts a wall or a core shortly after entering the cavity. Unrestricted flow, i.e. jetting, is to be avoided under all circumstances. The optimum ratio of sprue diameter to wall thickness must be carefully determined and employed to obtain surfaces with optimum visual appearance. When moulding thin walled parts with large surface areas, a film gate is often used in order to achieve a parallel orientation across the entire width, to achieve uniform shrinkage in the direction of flow and the transverse direction and to prevent visual defects such as gate marks on the surface.

Figure 7: Pin gate

Figure 8: Submarine gate

Figure 9: Film gate


22 27

1. The Runner System in the Mould

Figure 2:Overview of runner system with individual components as designated inthe following text.

2. Balancing the Runner System

A balanced runner system in the mould is important in order to ensure that all cavities are filled evenly (see Figure 3).In an unbalanced system cavities closer to the sprue are overfilled and those further away are not filled completely (see Figure 4).

Figure 3: Balanced runner systemThe flow path from the sprue to the cavity is always the same distance.The primary and secondary runners are also properly dimensioned relativeto one another.

Hot-worked steels, e.g. 1.2343 or 1.2344 grades, are suitable for generalapplications. Cold-worked steels such as grade 1.2767 exhibit outstandingcompressive and flexural strength and as such are well suited e.g. forinjection moulding of articles over long, unsupported cores.1.2311 grades (suitable for surface graining) and 1.2312 grades (not suitablefor surface graining) are well suited for moulds for large-sized articles.Corrosion-resistant steels (e.g. 1.2083) are superb materials for precisionmultiple-cavity moulds as their outstanding properties (e.g. corrosion resistance,hardness, abrasion resistance) ensure long service life.

For more detailed information please consult your mould supplier.

9. Mould Surfaces and Demoulding

Parts made from THERMOLAST® compounds usually exhibit high surfacefriction. Soft compounds also tend to suction themselves to smoothmould surfaces. Spark-eroded moulds decrease adhesion to the mouldedpart and hence facilitate demoulding.

Ejectors should be selected in accordance with the hardness of the compoundprocessed. When processing soft grades, large-area ejectors arepreferable to ejector pins.

Due to the elasticity of THERMOLAST®, undercut parts can frequently beejected from simple undercut moulds without need for a pusher, i.e. bysimply pressing the parts out of the mould. Air-pressure supported ejectorsare beneficial with soft compounds and more pronounced undercuts.

When moulding coinjected articles please note: if the hard componentincorporates a polished surface (i.e. the bonding surface contacting thesoft component), this can impair adhesion. Improve adhesion by sparkerosion treatment of the surface (see Section 8. „Processing Informationfor Coinjection Moulding“, starting on page 34).


20 29

This is required to achieve long melt flow paths, particularly when mouldingvery thin-walled parts. Starting with these recommendations, users can conductoptimization trials to find the filling point providing high part quality.

The flow path diagrams shown below illustrate the effects of temperatureand injection pressure on flow behaviour for 3 high-viscosity THERMOLAST®

compounds.

We will be happy to provide more detailed information on the optimum injectionrate for your specific compound. You can also obtain this information formany compounds from the Processing Guide in the appendix to this brochureor at www.kraiburg-tpe.com.

7. Back Pressure and Screw Speed

Usually we recommend a back pressure of approximately 20 – 50 bar(285 – 710 psi). The screw speed should be between 25 and 75 rpm.

1. General Information

Coinjection moulding, also known as 2-component injection moulding,offers numerous benefits as it reduces the need for assembly work, shortensproduction times and therefore reduces manufacturing costs.Coinjected combinations of hard and soft materials are used most frequentlye.g. in fabrication of seals, anti-slip components and grip handles.THERMOLAST® compounds are also used in conjunction with differentcolouredthermoplastics for aesthetic reasons. In addition, the pleasantlysoft and warm feel of THERMOLAST® has led to its frequent use as a coinjectedsurface coating. The possibilities are endless; new ideas and shapeswhich can be realized using coinjection moulding processes are evolvingevery day.

2. Advantages of Coinjection Moulding:

allows different hardness and flexibility within same componentmore freedom in aesthetic design e.g. thanks to colour diversity,transparent surfaces or other interesting characteristics of otherTHERMOLAST® compoundshigher productivityreduced floor space requirementsno need for part assemblyquality control required for one article onlyreduced part weightadditional value for end users (design aesthetics, quality, function …)

THERMOLAST® in Injection MouldingMachines and Processing


18 31

1. Processing Machinery

THERMOLAST® compounds can be processed on standard injection mouldingmachines for thermoplastics incorporating 3 screw zones.Screws should have a compression ratio of at least 2:1 and an L/D ratio ofat least 20:1. Barrier screws may be required in certain cases, e.g. toachieve an increased plasticizing rate.Processing is possible with open nozzles. The use of shut-off nozzles anda backflow check valve at the tip of the screw can be advantageous.

2. Cleaning of Machines

Before processing THERMOLAST®, purge out the injection mouldingsystem with polypropylene. If another material is to be used afterwards,run system until empty and purge again with polypropylene.

3. Processing Parameters

The following sections 4. - 8. provide information and general recommendationsfor processing THERMOLAST®. Please keep in mind that yourexperience with your machines and the particular material processedshould always be taken into consideration as well. As THERMOLAST®compounds are frequently custom-developed to individual customerrequirements, differences in processing can result.

Our applications engineers will be happy to provide any advice you mayrequire and to come to your plant upon request to observe processing ofsample materials.

Adhesion is caused by intermolecular attraction (Van der Waals forces)and by molecular entanglement (interdiffusion).Van der Waals forces: attraction forces due to molecular interactionsInterdiffusion: mechanical, intermolecular entanglement of macromolecules driven by thermal energy. Sections of neighbouring macromolecules penetrate into each other, forming a mechanical connection.

A brief overview of THERMOLAST® bonding to a wide variety of thermoplasticsis given in “Table Comoulding Systems” on page 34.

6. Machinery for Coinjection Moulding

In general the information given before in this text in the section 1. ProcessingMachinery on page 18 applies also to coinjection.

Various options are available in fabrication of coinjected compositepartsas described below:

Maschine(s) Possible moulds Process Result

Coinjection mouldingmachine (with two injection units)

Coinjection pusher mouldCoinjection rotary table mouldCoinjection index plate

First material is injected,followed immediatelyby the other

Ideal conditions forexcellent adhesion

Transfer process usingtwo injection mouldingmachines

Two moulds with different cavities

Semi-finished part is transferred into the 2nd mould/injection moulding machine (by robot or by hand)

Good adhesion to cer-tain thermoplastics (see„Comoulding Systems“)

Transfer process usingone injection mouldingmachine (insert moulding)

Two moulds with different cavities

Intermediate storage ofsemi-finished part,mould is changed, 2ndmaterial is injected

Good adhesion to cer-tain thermoplastics (see„Comoulding Systems“)

THERMOLAST® in Injection MouldingMachines and Processing

16 33

5. Predrying

As THERMOLAST® is not hygroscopic, predrying prior to processing isnormally not required. Should condensation occur due to large temperaturefluctuations between transport, storage and/or production, we recommenddrying the material for 2 hours at 80 °C (175 °F).Adhesion-modified compounds should be pre-dried prior to processing inaccordance with the processing instructions (www.kraiburg-tpe.com).

6. Weldability

Most THERMOLAST® compounds are easy to weld (e.g. by hot plate welding).Very high seam strengths can be attained due to the material’s thermoplasticcharacteristics.Further information can be provided by your KRAIBURG TPE representative.

7. Contact Behaviour with Other Thermoplastics

In applications in which THERMOLAST® directly contacts other thermoplastics- except for plasticized PVC - no interaction (i.e. stress cracks, plasticizermigration) occurs between the adjacent materials.

Peel Test According to Renault D41 1916 Standard

test setup

adhesion to thermoplastics

On request we will be happy to provide coinjected sample plaques madewith materials you wish to evaluate.

A number of factors can significantly influence THERMOLAST® adhesionresults including the manufacturing process and process parametersused, part geometry and composition of the hard material. We thereforestrongly recommend tests under the actual conditions prevailing in theapplication.Please also note that the final adhesion quality is only achieved after astorage period of approximately 24 h.

Our application engineering department can provide advice on design,material selection and tests.

Product PropertiesImportant Additional Information

14 35

3. Weathering and Ozone Resistance

THERMOLAST® compounds are resistant to the effects of UV and ozoneas found in normal applications. Several compound series are availablewith additional weathering resistance for long-term outdoor use as providedby specially developed stabilization and colouring systems. Productsmade from these compounds fulfil demanding specifications in the automotiveindustry (e.g. Kalahari test, Florida test, VW PV 3930, 3929) andconstruction industry (RAL GZ 716/1 and CSTB certification for qualityassuredplastic window systems).We will be happy to send you data sheets providing more detailed information.

For a quick overview of the compound series which are particularly wellsuited for outdoor applications, visit www.kraiburg-tpe.com.

1. Packaging and Storage

THERMOLAST® compounds can be supplied in 20 or 25 kg (44 or 55 lb)sacks, bulk octabins or in bigbags. The material should be kept in a dark,dry area if it will be stored for a long time prior to use.PLEASE NOTE: When exposed to high temperatures, super-soft compoundsmay agglomerate which can result in blockage of conveying systems.Therefore high temperatures must be avoided in transport and storage. Wewill be glad to provide more information in this regard on request.

2. Recycling

THERMOLAST® scrap can be recycled without difficulty, as is the case withscrap from other thermoplastics. We recommend a maximum recycleblend-in rate of 15% relative to virgin material.

The bar graphs below illustrate the change in mechanical values as a functionof process cycles for injection-moulded product consisting of 100%recycle. Overall the material was injection moulded 9 times and ground betweeneach cycle, i.e. ground a total of 8 times.

Tensile strengthHardnessElongation at break

Mechanical properties after X process cycles, given as % of original value.

Always use the processing temperatures for adhesive compounds given at www.kraiburg-tpe.com.Inject the THERMOLAST® compound processed initially at a medium rate and then increase the rate as required for optimum part quality.Use the correct tooling temperature as required by the thermoplastic processed and the wall thickness of the article moulded.In general do not use hold pressure as it can cause material displacement at the bond interface, i.e. destruction of adhesion achieved immediately in coinjection.Do not use any demoulding aids such as lubricants, etc.Increase the surface area of the bonding surface (e.g. by spark erosion treatment).Improved results may be achieved if the two materials are injected into the mould from opposite directions.

Further advice can be found in our Injection Moulding Trouble Shooter onpage 38.

Special points with regard to transfer processes:The surfaces of the semi-finished part moulded onto must be absolutely free of grease and dust (machine operators should wear gloves if necessary).Semi-finished parts which are processed after intermediate storage normally should be preheated prior to encapsulation or coating with THERMOLAST®. The preheating process should last for only a short period of time (very important especially in the case of semi-crystalline thermoplastics) and should heat the surface of the part only (use e.g. IR heating, surface temperature attained should be approx. 80 °C - 100 °C).

Please note our recommendations on the previous page contained in the rightcolumn of the “Table Comoulding Systems” (Transfer Processes ProvidingGood Adhesion Results).

Special points with regard to shrinkage:

In the case of hard/soft parts, the shrinkage is generally impeded due to adhesi-on to the pre-injected part, i.e. the shrinkage values of the hard material play adetermining role. Therefore, it is important that the stability of the hard preinjec-ted part is sufficient. Through the injection of the soft component, internalstress that was built up in the pre-injected part would cause warpage of thefinished part. Integrating reinforcements (reinforcing ribs) into the hard partmay be necessary, especially in the case of very thin-walled parts and/or extensi-ve coverage with TPE.Please note that shrinkage will vary depending on the particular compound processed. Your KRAIBURG TPE representative will be happy to provide more information relating to your specific application.

Product PropertiesEnvironmental Resistance

Important AdditionalInformation

12 37

4. Compression Set

THERMOLAST® is available in a wide range of compounds with optimizedcompression set for use in both 1-component and 2-component injectionmoulding processes. The bar graphs below compare compression setof a standard THERMOLAST® K compound, a typical EDPM/PP and aTHERMOLAST® V compound - each with a Shore A hardness of 70 - atvarious temperatures.

Please consult our data sheets for detailed information and mechanicalproperty values or contact us for more particulars concerning compoundswith optimized compression set.


Part distortion Too much orientation 1. Increase melt and mould temperature.2. Reduce injection rate.

Part is over-packed 1. Reduce back pressure.2. Match injection time to mould fill time.

Uneven mould fill 1. Change gate locations.2. Ensure uniform mould temperature.3. Increase injection rate and back pressure.

Black specks orundispersed particles

Contamination 1. Purge with high-MFI PP or HDPE.2. Check that colour concentrate is based on PP or PE, not PVC.

Sticking in mould Part is too hot 1. Reduce barrel and nozzle temperatures.2. Reduce mould temperature.3. Increase cooling time.

Part is over-packed 1. Reduce shot weight and find correct fill point.

Mould design 1. Increase draft angles.2. Use non-stick surface treatment.3. If necessary, erode mould.

Clump formationat gate

Moisture 1. Dry pellets.2. If using vented screw, check for obstruction of vent.3. Add vacuum assist to vents.

Flow lines Melt and / or mouldtoo cold

1. Increase barrel and nozzle temperatures.2. Increase melt and / or mould temperature.3. Increase injection rate.4. Increase screw speed and back pressure.5. Check suitability of screw.

Mould design 1. Change gate location.2. Enlarge gates.3. Enlarge runners.4. Add additional flow-restricting zones (e.g. sprue pullers) to runners.

Voids(not to be confusedwith air entrapment)

Melt freezes too quickly 1. Increase mould temperature.2. Increase screw speed and back pressure.

Moisture 1. Dry pellets.2. If using vented screw, check for obstruction of vent.3. Add vacuum assist to vents.

Back pressure too low 1. Increase back pressure.

Product PropertiesPhysical Values

10 39

Further characteristics, irrespective of industry an application field:

Adhesion to all common engineering thermoplastics (in conformance with Taisei patents*)Optimized compression setEasy to colourTransparentVery soft but with excellent mechanical propertiesHigh elasticityExcellent resilienceEtc.

IMPORTANT NOTE: The information provided here shows only some ofthe industries and application fields in which THERMOLAST® compoundsare used and an overview of their important properties.More detailed information is available at www.kraiburg-tpe.com.

5. Custom Engineered TPE

Many products, particularly those intended for new application fields, cannotbe realized with materials from standard product ranges. Whether usedin existing or new applications, sometimes a „perfect“ compound is neededto meet specific requirements.We invite you to benefit from our many years‘ experience in tailor-maderesin development. Contact us and together we‘ll find the ideal solution foryour product.

Here are some of the properties that can be modified to meet your requirements:HardnessDensityTactile feelFlow characteristicsDamping characteristicsColourResilienceUV-resistanceElasticityAbrasion resistanceEtc.

We will be happy to assist you in selecting the compounds which best fityour specific needs. We look forward to your enquiry.

1. Machines and Processing

Machine specifications:

Standard injection moulding machineCompression ratio: at least 2:1L/D ratio: at least 20

Purging materials:

PP

Process parameters:

Melt temperature: please refer to processingMould temperature: instructionsInjection pressure: at www.kraiburg-tpe.comInjection rate:

Back pressure: 20 – 50 bar (285 – 710 psi)Screw speed: 25 – 75 rpmHold pressure: if possible, noneHold time: as short as possible

IntroductionCompounds Summary Injection Moulding

THERMOLAST® in Injection Moulding

8 41

1. Compound Composition

THERMOLAST® compounds are formulated from a combination of rawmaterials including, for example:

Polymer: hydrogenated styrene block copolymerThermoplastic carrier: polyolefinPlasticizer: paraffinic white oilInorganic fillersOther additives

2. Significant Benefits in Processing

THERMOLAST® compounds are supplied as pellets and can beprocessed directly as delivered without requiring additives of any kind.THERMOLAST® offers the following advantages in processing ascompared to conventional elastomers:

No vulcanization requiredNew machine investments normally not requiredCan be processed by conventional plastics processing methodsSimple to processShort cycle timesExcellent heat resistance, i.e. large processing windowLow energy consumptionProduction scrap can be re-used by direct recyclingProcessing parameters can be modified to enhance product quality and reduce dimensional tolerancesEasy to colourOutstanding adhesion to virtually all thermoplastics in coextrusion and multicomponent injection moulding processes

1. Machine Specifications

Extrusion of THERMOLAST® compounds normally does not require useof special extruders. Standard extruders (e.g. universal or polyolefinextruders) designed for conventional plastics can be used to processTHERMOLAST® compounds in most cases. Some restrictions apply toPVC extruders. Please contact us for futher information.

2. Cleaning of Machines

Before processing THERMOLAST® compounds, urge the extruder withpolyethylene or polypropylene. Purge particularly thoroughly if the materialrun beforehand was PVC.

If another material is to be processed afterwards, run system until emptyand purge again with PE or PP.

3. Screws, Screens, Breaker Plate

Experience has shown that 3-zone screws are best suited for processingTHERMOLAST® compounds. The screw length should be at least 25 D.The compression ratio should be at least 3.5 : 1. The screw must be ableto provide sufficient shearing. A breaker plate and a screen pack are normallyrecommended in the extruder configuration in order to increasepressure.

4. Process Parameters

The following sections 5. - 7. provide information and general recommendationsfor processing THERMOLAST® compounds. Please keep inmind that your experience with your machines and the particularmachine processed should always be taken into consideration as well.As THERMOLAST® compounds are frequently custom-developed to individualcustomer requirements, differences in processing can result.

Our applications engineers will be happy to provide any advice you mayrequire and to come to your plant upon request to observe processing ofsample materials.

IntroductionCompounds

THERMOLAST® in ExtrusionMachines and Processing

6 43

1. Extrusion Dies

Simple matrix dies will suffice for processing THERMOLAST® compoundsin many applications. The die land should be as short as possible, i.e.max. 3 - 4 mm (0.12 - 0.16 in.), particularly if the surfaces of the die arenot finely polished.

More elaborate multi-component dies with flow correction capability providebenefits including reduced machine direction shrinkage and reducedprofile distortion. They also allow attainment of higher production rates.When extruding hollow profiles, internal air support can be advantageous.

1. Combination Possibilities

THERMOLAST® compounds can be coextruded with many different kindsof thermoplastics. Compounds are offered in a wide range of hardnessratings and other physical properties for adhesion to:

PPPEABSPSPCrigid PVC

Of course, THERMOLAST® compounds can be coextruded together aswell. The wide spectrum of THERMOLAST® extrusion compounds availableprovides numerous possibilities of combination (hardness, transparency,colour, feel, ...).

Figure 1:Positioning of TPEs within the plastics family.

Introduction Polymer Family Tree Dies

Coextrusion

4 45

1. Machines and Processing

Machine specifications:Universal or polyolefin extruders with 3 screw zonesCompression ratio: min. 3.5 : 1L/D ratio: min. 25

Purging materials:PE or PP

2. Process Temperatures:

Feed zone: 140 – 160 °C (285 – 320 °F)Compression zone: 150 – 170 °C (300 – 340 °F)Metering zone: 160 – 180 °C (320 – 355 °F)Extruder head: 170 – 180 °C (340 – 355 °F)Die: 180 – 220 °C (355 – 425 °F)

3. Dies

Simple matrix die is sufficient in most casesDie land: max. 3 – 4 mm (0.12 – 0.16 in.)Die temperature185 °C (355 °F)

Polymer Family Tree _____________________________________Thermoplastics – Elastomers – Thermoplastic Elastomers _______Compounds _____________________________________________ 1. Compound Composition 2. Significant Benefits in Processing 3. Series Compounds – Significant Features ______________ 4. THERMOLAST® Compound series 5. Custom Engineered TPE ______________________________

Physical Values __________________________________________ 1. Hardness 2. Tensile Strength and Elongation at Break 3. Service Temperatures 4. Compression Set ___________________________________Environmental Resistance _________________________________ 1. Chemical Resistance 2. Behaviour in contact with Acrylic Paint 3. Weathering and Ozone Resistance ___________________Important Additional Information 1. Packaging and Storage 2. Recycling 3. Environmental Compatibility _________________________ 4. Colouring 5. Predrying _________________________________________ 6. Weldability 7. Behaviour in contact with Other Thermoplastics 8. Adhesive Bonding and Surface Decoration ____________

Machines and Processing _________________________________ 1. Processing Machinery 2. Cleaning of Machines 3. Processing Parameters 4. Barrel and Melt Temperatures ________________________ 5. Mould Temperature 6. Injection Pressure and Injection Rate 7. Back Pressure and Screw Speed ______________________ 8. Hold Pressure and Hold Time ________________________Moulds _________________________________________________ 1. The Runner System in the Mould 2. Balancing the Runner System 3. Gate Points ________________________________________ 4. Sprue ____________________________________________ 5. Primary and Secondary Runner System 6. Types of Gates _____________________________________

Introduction

Product Properties

THERMOLAST®

Injection Moulding

678

9

10

11

1213

14

15

16

17

18

19

202122

2324

25

Table of contentsSummary Extrusion

THERMOLAST® in Extrusion

The information in this publication is based on our current knowledge and experience. In view of the many factors that may affect processing and application, this information does not relieve processors of the responsibility to carry out their own tests and experiments; neither do they imply any legally binding assurance of certain properties or of suitability for a speci-fic purpose. It is the responsibility of those to whom we supply our products to ensure that any proprietary rights and existing laws and legislation are observed.

2 47

Europe

KRAIBURG TPE GmbH & Co. KGFriedrich-Schmidt-Str. 284478 Waldkraiburg, GermanyPhone +49 (0) 86 38 / 98 10 - 0Fax +49 (0) 86 38 / 98 10 - 3 10E-Mail [email protected]

Americas

KRAIBURG TPE Corporation2625 North Berkeley Lake RoadSuite 100Duluth, GA 30096, USAPhone +1 678 584-5020Fax +1 678 584-0500E-Mail [email protected]

Asia/Pacific

KRAIBURG TPE TECHNOLOGY (M) SDN.BHD.Lot 1839 Jalan KPB 6Kawasan Perindustrian Balakong43300 Seri Kembangan, Selangor,MalaysiaPhone +603 8962 1393Fax +603 8961 - 9892 / - 9884E-Mail [email protected]

KRAIBURG TPE China Co Ltd148 Electric Road, North PointRoom 2805, Hong Kong, ChinaPhone +852 2164 4882Fax +852 2164 4883E-Mail [email protected]

Additional addresses of KRAIBURG TPE local offices and sales representa-tives can be found at www.kraiburg-tpe.com.

KRAIBURG TPE locations

Date post:	22-Jul-2018
Category:	Documents
Upload:	vuongtruc
View:	212 times
Download:	0 times

Product Properties and Processing - Kraiburg...

Documents